There are many reasons why it may be desired to mix additives or supplements with a liquid contained in a container. One example relates to beverages. In a health sense there may be the desire to add dietary supplements to water to create a healthy mixed drink. In the wine industry adding certain additives to wines will neutralize the effects of preservatives and other chemicals used in the wine making process that can cause unpleasant side effects in some people.
In another example, domestic cleaning products or fertilizers and the like used in gardening are sometimes activated by adding an activating substance to a base liquid.
Dispensers can be employed to dispense and release an additive into a container containing a base product, such as water, and it has been known to incorporate these dispensers into closures for containers. However such dispensers can be unreliable as well as expensive to produce as they take the form of complex mechanisms, which can also be unsightly and intrusive on the aesthetics of a product.
It is these considerations that have brought about the presently described cap for a container.